Means for finishing grooved hollow metal bodies



Aug. 23, 1938. CUPPERS 2,127,809

MEANS FOR FINISHING GROOVED HOLLOW METAL BODIES Filed Dec. 18, 1956 Patented Aug. 23, .1938

UNITED STATES PATENT OFFICE MEAN S FOR FINISHING GROOVE!) HOLLOW METAL. BODIES Paul Ciippers, Augsburg, Germany, assignor to Maschineniabrik Augsburg-Number; A. G., Augsburg, Germany, a corporation of Germany Application December 18, 1936, Serial No. 116,548 InGerinany December 18, 1935 80lalms. (Cl. 29,90)

. powdered emery is glued, but these methods suffer from the drawbacks that the grooves are either only polished, without thesimultaneous removal therefrom of any cracks or other flaws, or that, because of insufficient guidance within the grooves, the latter are rendered uneven in width. Moreover, there was the risk of impurities being introduced into the grooves, which were treated while being in a horizontal position.

To avoid or entirely eliminate those drawbacks is the purposeof the present invention, which has for its object to devise a method and means for perfectly grinding and finishing the grooves or key-ways provided in the-interior of hollow metal I bodies.

According to this invention, 1' use for the grinding of the grooves or keyways especially shaped grinding elements and for smoothing the bottoms of the grooves or keyways especially constructed pressure rolis. The grinding elements are oi rhombold shape, and their widest portion is a trifle narrower than the grooves to be finished so that the grinding elements as they are drawn or pushed through helically extending grooves, always bear against the base and one side of the grooves. In order to make the grinding elements or pressure rollers suited to every kind of twist of the grooves and even to varying twists of the same bore, 1 pivotally support the holders for the grinding elements or pressure rollers so as to enable a pressure-roller holder and Fig. 5 a transverse section through the same.

At l in Fig. 1 is shown a casing having in its central portion a number of slots 1'. In these slots are mounted sliding rails shown at 2, which by means of resilient rings 3 and l are held in the casing l. The rails 2 are provided with inclined faces 5 and 6 which bear against cones 1 and 8 provided on an adjustable mandrel 9.

At ID are shown holders to which the grinding stones II are cemented and which are provided with stems I2, whereby they are pivotally mount- I ed in the sliding rails 2. At its opposite ends, the holders ill have secured to them a resilient bar shown at i3, which bars each carry a block it. These blocks act as guides for guiding the grinding'stone in the groove to be finished. At i5 is shown a guide element, mounted on the lower portion of the casing i and held thereon by means of a nut shown at IE.

At the other end of easing I is provided a capnut H which extends over the end of the casing that is formed with screw-threads to receive the nut. The not I! is prevented from'rotation by a clamping member it which by means of a wedge i9 and a pressure screw is pressed against the female threads of nut ii. By reason of the pressure exerted by a screw shown at 20 against a slanting face 22 provided on the wedge 19, the latter is moved towards the right in Fig. 1, thus forcing with its wedge-face ii the clamping memher it outwardly. Between the cap-nut i1 and a flange it on the hollow shank 2d of a chuck (not shown), on the one hand, and a ring 25 secured to the shank it, on the other hand, there is provided a pressure ball-bearing shown at 26 and Ti respectively, permitting a rotation of the casing i relative to the shank it of the chuck. Within the hollow shank lid is secured by screw-threads a spindle 29, which by means of a divided collarnut shown at it is connected with the adjustable mandrel 9 holding the latter in its adjusted position. Intermediate the mandrel 9 and the spindle it is provided a ball shown at i i, facilitating rotation of the parts relative to each other.

By means of a chuck not shown the casing i. is connected with a drawing spindle (not shown) whereby the device, after the guide blocks II have first been introduced into the grooves to be finished, is repeatedly drawn or pushed back and forth through the hollow metal body.

The positioning of the grinding stones ll may be easily accomplished as follows;

First, the screw 20 is loosened, whereby the tension between the wedge l9 and the clamping member l8, on the one hand, and between the latter and the cap-nut H, on the other hand, is sufiiciently relaxed to enable the cap-nut to be screwed along the screw threads of casin: I, whereby the cap-nut becomes displaced, resulting in a corresponding displacement of the hollow shank 2!, of the spindle 29 secured therein and of the adjustable mandrel 9. Depending on the direction of movement of the mandrel 9, its conical portions 1 and 8 wii cause the sliding rails 2 carrying the grinding stones H to move inwards or outwards in the slots of the casing. In this manner the grinding stones l I held by the holders l0 pivotally carried by the rails 2 can be posi tioned to any desired outer diameter.

If the device is to be used for pressing the bottoms of the grooves for smoothing the same, pressure rollers as shown at 33 in Figs. 4 and 5 are substituted for the grinding stones H. But instead of the holders shown at l0 in Figs. 1 and 2, especially designed holders shown at 32 in Figs. 4

and 5 may be used, which in a similar way as theholders l0 are pivotally mounted in the sliding rails 2. To these holders 32 also guide-blocks, like the guide-blocks l4 shown in Fig. 1, are secured by means of resilient bars, such as the bars l3 in Fig. 1, which bars are secured in slots 34 provided in the holders 32 (Fig. 4).

While I have shown and described an embodiment of my invention, I do not, of course, intend to limit myself thereto, since my invention is capable of various embodiments and modifications falling within the scope of this invention.

I claim:

1. In a device of the kind described, in combination a casing, a plurality of tools of rhomboid shape movably mounted at the periphery of said casing, the greatest width of said tools in their center being smaller than the width of the grooves to be finished, and guiding means for said tools.

2. In a device of the kind described. in combination a casing, holders pivotally mounted at the periphery of said casing, tools carried by said holders, and guiding means on said holders for said tools.

3. In a device of the kind described, in combination a casing provided in its periphery with slots, sliding rails mounted in said slots, holders pivotally carried by said sliding rails, tools secured to said holders, and resilient guiding means on said holders for said tools.

4. In a device of the kind described, in combination a casing provided with slots, sliding rails mounted in said slots, holders pivotally carried by said sliding rails, tools secured to said holders, resilient guiding means on said holders for said tools, a mandrel in said casing axially movable therein in cooperative relation to said sliding rails for positioning them circumferentially relative to said casing, and means for axially displacing said mandrel.

5. In a device of the kind described, in combination a casing provided with slots, sliding rails mounted in said slots, holders pivotally carried by said sliding rails, tools secured to said holders, resilient guiding means on said holders for said tools, a mandrel axially movable in said casing and having conical portions bearing against corresponding faces on said rails for circumierentially displacing said rails in said slots relative to said casing, and means for axially displacing said mandrel.

6. In a device of the kind described, in combination a hollow shank adapted to be operatively connected with a chuck, a spindle secured within said hollow shank, a casing connected with said shank and provided with slots, sliding rails mounted in said slots, holders pivotally carried by said rails, tools secured to said holders, resilient guiding means on said holders for said tools, a mandrel axially movable in said casing in cooperative relationship to said sliding rails for eircumferentially displacing the same relative to said casing, and means operatively connecting said mandrel with said spindle, said connecting means including a ball permitting a relative rotary movement between said mandrel and said spindle.

'7. In a device of the kind described, in combination a hollow shank adapted to be operatively connected with a chuck, a spindle secured within said hollow shank, a casing provided with slots, 1

sliding rails mounted in said slots, holders pivotally carried by said rails, tools secured to said holders, guiding means on said holders for said tools, a mandrel axially movable in said casing in cooperative relationship to said sliding rails for circumierentially displacing the same rela tive to said casing, means operatively connecting said mandrel with said spindle, and means connecting said casing with said shank, said means including ball-bearings so as to permit a relative twist between said casing and said shank.

8. In a device of the kind described, in combination a hollow shank adapted to be operatively connected with a chuck, a spindle secured within said hollow shank, a casing provided with slots, sliding rails mounted in said slots, holders pivotally carried by said rails, tools secured to said holders, guiding means on said holders for said tools, a mandrel axially movable in said casing in cooperative relationship to said sliding rails for circumferentially displacing the same relative to said casing, means operatively connecting said mandrel with said spindle, a cap-nut engaging a flange on said'shank and screw-threads on said casing thereby connecting these parts, and ball-bearings in said connection so as to permit a relative twist between these parts.

PAUL ciiPPERs. 

